Socket for electric lamps



April 24, 1928. 1,666,974

. F. J. MILES ET AL SOCKET FOR ELECTRIC LAMPS Filed Nov. 14, 1924 III- INVEN'I'ORS 1 LAVA. LQK. 3 TYUA I) Qua la, of'h son ATTORA l-IY ber of parts,

Patented Apr. 24, 1928.

UNITED STATES PATENT OFF 1 FREDERICK J. MILES AND noNALn o; THOMPSON, E NEWARK, {NEW JERSEY, AS-

SIGNORS, BY MESNE ASSIGNMENTS, TO EUGENE SULLIVALLOF NEw YORK, N. Y.

SOCKET FOR ELECTRIC AMPS.

Application filed November 14, 1924. Serial No. 749,907,

Our invention relates more particularly to lamp sockets employed where'vibration 'is present and whereit is necessary to guard against the lamp working loose in the socket, and more particularly for use on vehicles, such as automobiles, and especially for use in signal devices for such vehicles.

The object of our invention is v to provide a socket which will insure perfect contact and guard against the lamp working loose, thereby avoiding poor contact,.or'a contact becoming entirely separated, and also to insure clean contacts. 'A further object is to provide a construction having-the least numreadily made and assembled, and which will permit extremely low cost of production. i g V To accomplish our objects we have 'de'- signed a socket having only threeparts, and in which screws, rivets and brazed or. soldered joints are entirely dispensed with. These parts comprise a base plate of insulating material and two contact members, one contact member being the socket or sleeve for the lamp and the other beingthe bottom contact member. The socket member is a tubular metal piece having two oppositely located bayonet-lock slotsand two projecting lugs by means of which the socket is clamped to the base. The bottom contact member is stamped from sheet metal and bent into shape so as to present three elements: first, the contact end, which is bent into S-shape and which projects through a gap into the socket member; sec- 0nd, a clamping element consisting of two laterally projecting lugs which are bent downward to pass through two slots in the base plate and again bent to clamp the contact piece in position; and third, at the outer end two upwardly projecting lugs for clamping a circuit'wire connection. [I

In the drawing, Figure 1 is an elevatlon of the socket with a lamp mounted therein and a circuit wire connected between the clamping lugs of the bottom contact member; Figure 2 is a top plfiILVlGW of the socket; Figure 3 is a vertical section ofthe line 33 of Figure 2; Figure 4: a bottom plan view;Figure 5 a central vertical section through Figure 2 taken at right angles to the line 3-3 and showing the clamping lugs for the wire connection in the open position; Figure 6 a vertical section lllustrating the clamping lugs tor the conductor in the closed position; and Figure 7 a cross section of the line 77 of Figure 6; Reterrmg now to the drawings, 10 inclicates the metal sleeve-or socket member hav- 7 ing bayonet type slots as indicated at ll and 12 adapted to receive'the'locking pins 14 projecting, laterally from a'metallic collar 15' on the base of lamp 13 and which col-l'ar constitutes one'contact terminal of the lamp. The sleeve 10, at the end which is seated upon the base plate of insulating material, is provided, with two oppositely located gaps 16 and 17 andpr'eferably so located as to be diametrically opposite to the bayonetsleeve in line with the two bayonet-slots are slots, and projecting from the end of the lugs 18 and 19 which are inserted through slots '21 and 21in the base plate and bent over as 'shownin Figures 3' and at to clamp the sleeve member 10. firmly upon the base plate, The base plate 20 may be of any desired shape but preferably is or the shape shown in Figures 2 and 4t and is provided with two centrally located slots 21'and 21 for the socket. member already referred to, and twosimilar slots 28 and'28 located closer together, and near one end of the base plate for receiving the bottom contact lugs. The base plate also is provided with holes to receive pins or screws whereby same may be secured to any desired support or fixture or within an automobile lamp chamber.

The bottom contact member oft-he socketis stamped in one piece from pliable sheet metal such asbrassaor copper in the form of a long narrow strip with four projecting lugs 26,27, 31, and 32, lugs 26 and 27 being bent downward for the purpose of passing through slots 28 and 28 in the base plate and long'enoughto be bent over as indicated I in Figure 4 so as to clamp this contact mem her in position on the base plate, The otherv two lugs 31"and 32 .are bent upward prepared to IGCGlXt-L acircuitfwire.and clamped as will be presently explained. The ppssite end of the'contact member isipreterably bentinto approximately S-shape as best'indicated in Figure 5, the lower portion thereof being approximately parallel with the base plate and'having a return bend 23, and

,a second bend which forms the contact 24;

which asshown is positioned centrally wit-hin the sleeve 20 so as to make contact with the bottom terminal 22 of the lamp base as indicated in Figure 5. The Contact end 24 v 1,eee,e74

is so positioned vertically within the sleeve 10 that when the lamp is inserted the bot tom contact 22 of the lamp will engage the contact 24 before the pins 14 reach the looking ends of the bayonet-slots so that as the lamp is pressed into locking position the spring contact 24 will be under considerable pressure tending to push the lamp upward and holding lamp pins 14 firmly within the bayonet-lock. lVhen thus inserting the lamp and applying pressure to the spring contact it will readily be observed that the act of bending the bottom contact will produce a relative rubbing action between contacts 22 and 24: thus insuring a: clean con tact. The purpose in having two gaps lo and 17 in'the sleeve member 10 is first, to provide an entrance for the spring contact member 24 and secondly, to guard against the curved portion 23 coming in contact with the sleeve. Another advantage in providing the two gaps is that no mistake can be made in mounting the sleeve upon the base plate since it makes no difference which of the two gaps 16 and 17 are adjacent to the slots 28 and 28 of the base plate. For the purpose of facilitating the attachment of a conducting wire to the bottom contact strip the hole 30 positioned between the lugs 31 and 32 is provided and when attaching a circuit wire the end is bared of insulation and inserted downward through the hole 30 and then bent under and over the end of the plate and back between lugs 31" and 3'12 parallel with the covered portion at the conductor as shown'in Figures 5 and (3 and thereupon lug 31 is bent firmly against the conductor, a pair of ordinary pliers being employed for the purpose, and then lug 82 is similarly bent over, overlapping lug ill as illustrated in Figures 6 and 7. Thus a firm contact is obtained without the use or screws, or solder.

This form o1 socket is especially designed for use where the fixture or other device upon or within which the socket is mounted, forms part of a grounded circuit, and with this in view the lugs 18 and 1.9 aredesigned to be held in contact with such metallic support when. secured in place by screws or pins passed through the holes in the base plate.

From the foregoing it may be observed that the construction of our improved lamp socket is extremely simple and as above stated comprises only three parts and does away entirely with screws, rivets or soldered joints, and it is also evident that this form ally projecting pins of a lamp base, a slot or gap for receiving the other contact element, and two oppositely located lugs adapted to pass through slots in the base piece and to be bent over for clampingsame to the base piece and which lugs are adapted to make contact with a metallic piece included in a grounded circuit; and three, a spring contact member projecting into said cylindrical piece and having downwardly projecting lugs passing through slots in said base piece and bent over to clamp same in position and also having lugs for clamping a circuit wire to said contact member.

2. An electric lamp socket consisting of three pieces, one, a basemember of insulating material having a plurality of slots formed therein; two, a cylindrical socket contact piece having; two oppositely located bayonet-iock slots adapted to receive the laterally projecting pins of a lamp-base, two oppositely located gaps in the lower end of said socket piece and positioned dian'ietrically opposite to the bayonet-loo slots, two oppositely located lugs projecting from the lower end and adapted to pass through slots in the base piece and to be bent over for clan'iping said socket and base together, and which lugs are adapted to make contact with ametallicpiece included in a grounded circult; and three, a spring contact piece projectin intosaid socket member through one of the and having dow'ni'vardly projecting lugs passing through slots in said base and bent over to clamp same in posi tion, lugs at the outer end for clamping a circuit wire thereto and the inner or contact .end of said piece being bent into the form of a letter S. o

This specification signed this 13th day of November, A. D. 19%.

FREDERICK J. MILES DONALD C. THOMPSON. 

